I refer to https://bugzilla.redhat.com/show_bug.cgi?id=569098 > Our official policy is that doing installs / upgrade on degraded raid sets > is not supported. This has always been the case, if upgrades on degraded > raid happened to work in the past that was mostly luck. Although this might be the case, it has worked well for me up until FC10. When doing the upgrade from FC10 -> FC12, the installer refuses to use the degraded RAID1 sets available. When I activate the RAID1 sets manually, the installer finds the installed system and proceeds with the upgrade. Splitting a RAID1 set during upgrade is extremely useful it allows a fall back position should the upgrade fail. After all, the first step in the Fedora guidelines for performing an upgrade is to perform a _backup_ ! I do realise that RAIDn (n > 1) sets may be less useful. If there are system concerns about using degraded sets, perhaps they can be alleviated by either: a. Offering an option on the installer GUI to activate degraded sets, or b. Allowing a kernel command line option to activate degraded sets
*** This bug has been marked as a duplicate of bug 105598 ***